Implant sleeve and method

ABSTRACT

Several embodiments of an implant sleeve are shown for use with implants inserted through a wound into a surgical site. In some embodiments, the sleeve is useful to protect mating implant components from contamination during insertion through the wound. In other embodiments, the sleeve is useful to clean components that have become contaminated during insertion.

FIELD OF THE INVENTION

[0001] The present invention relates to sleeves for orthopaedic implantsand their method of use.

[0002] BRIEF DESCRIPTION OF THE DRAWINGS

[0003] Various embodiments of the present invention will be discussedwith reference to the appended drawings. These drawings depict onlyillustrative embodiments of the invention and are not to be consideredlimiting of its scope.

[0004]FIG. 1 is an exploded perspective view of an illustrativeembodiment of a sleeve according to the present invention shown withmodular implant components.

[0005]FIG. 2 is a perspective view of the sleeve of FIG. 1 assembledwith the components of FIG. 1.

[0006]FIG. 3 is an exploded perspective view of an illustrativeembodiment of a sleeve according to the present invention shown withmodular implant components.

[0007]FIG. 4 is a perspective view of the sleeve of FIG. 3 assembledwith the components of FIG. 3.

[0008]FIG. 5 is an exploded perspective view of an illustrativeembodiment of a sleeve according to the present invention shown withmodular implant components.

[0009]FIG. 6 is a perspective view of the sleeve of FIG. 5 assembledwith the components of FIG. 5.

[0010]FIG. 7 is an exploded perspective view of an illustrativeembodiment of a sleeve according to the present invention shown with animplant.

[0011]FIG. 8 is a perspective view of the sleeve of FIG. 7 assembledwith the implant of FIG. 7.

[0012]FIG. 9 is a perspective view of an illustrative embodiment of asleeve according to the present invention shown on an implant.

[0013]FIG. 10 is a side elevation view of an illustrative embodiment ofa sleeve according to the present invention shown on an implant beinginserted into a femur.

[0014]FIG. 11 is a side elevation view of an illustrative embodiment ofa sleeve according to the present invention shown on an implant.

DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

[0015] Several illustrative embodiments of an implant sleeve aredescribed for use with implants inserted through a wound into a surgicalsite. In some embodiments, the sleeve is useful to protect matingimplant components from contamination during insertion through thewound. In other embodiments, the sleeve is useful to clean componentsthat have become contaminated during insertion. The components includemating surfaces of mechanical assemblies for joining multiple implantcomponents together. The sleeve prevents or removes contamination thatwould interfere with the secure joining of the components. The matingcomponents also include cemented anchoring surfaces to be inserted intoa mass of cement placed at the surgical site or bone growth anchoringsurfaces to be pressed against the bone to receive bone growth. Thesleeve prevents or removes contamination that would interfere with thesecure adhesion of the cement to the components or that would interferewith bone growth. The sleeve of the present invention is useful in avariety of surgical situations where delivering at least a portion of animplant to a surgical site free from wound contamination is desired. Itis particularly useful where implantation is conducted through a smallincision, as in minimally invasive surgery. With a small incision, is itmore likely that implant surfaces will contact the soft tissues andfluids around the surgical wound and become contaminated.

[0016]FIGS. 1 and 2 show an illustrative embodiment of a sleeve for animplant. Then implant includes a hip stem 2 having a shaft 4 forinsertion into the intramedullary canal of a femur and a female taper 6having an internal taper engaging surface for receiving a modular headand neck 8 for articulation with an acetabulum. The modular head andneck 8 has a smooth articulating head 10 and a male taper 12 having anexternal taper engaging surface. The male taper is received by thefemale taper 6 with their engaging surfaces in overlying engagement. Theillustrative tapers 6, 12 form a locking junction that can be locked byimpacting them together. The sleeve 14 includes a sidewall 16 forming ahollow cylinder with opposite open ends 18, 20. The sleeve 14 can bemade from a variety of materials. In the illustrative embodiment, it isshown as a woven or knit, absorbent fabric than can be fit over the maletaper 12 similar to a sock. The structure of the fabric allows it tostretch to fit over the male taper 12 in close-fitting relationship. Thefabric can be made from any suitable natural or synthetic fiber. Othermaterials can be substituted for the woven fabric shown such as anon-woven fibrous sheet, a polymer film, a foil, a laminate, or othersuitable materials. The sleeve 14 can stretch to allow its removal or itmay be made with a frangible portion to break and separate as it ispulled away from the taper. One end 18 of the sleeve 14 may also beclosed to protect the end of the male taper 12. If the end 18 is closed,it can be made with a frangible portion so that it will come open uponremoval to facilitate removal of the sleeve 14. A frangible portion fora sleeve can be made in several ways, including using a materially thatis inherently thin enough or weak enough to break when it is pulled suchas a loosely twisted fibrous material or a thin film. A frangibleportion can also be made by partially cutting through a portion of thesleeve or heat crimping a portion of the sleeve. The sleeve can be madeto be frangible generally, or at a specific location.

[0017] In use, the sleeve 14 is slipped over the male taper 12 to coverat least a portion of the taper. The at least partially covered taper 12is then placed near the female taper 6. The sleeve is gripped by one end20 and pulled from the male taper 12. The tapers are then impacted andlocked together. A head and neck 8 having a male taper 12 and a stem 2having a female taper 6 are shown. The inventive sleeve 14 will workequally well with a head having a female taper and a stem having a maletaper.

[0018] In one embodiment, the partially covered taper 12 is looselyinserted into the female taper 6 with the sleeve 14 positioned betweenthe overlying taper engaging surfaces. Prior to locking the tapers 6, 12together, the sleeve is gripped by one end 20 and pulled 22 from betweenthe tapers to wipe the taper surfaces clean just before the tapers arelocked together. The sleeve 14 can be gripped with a pair of forceps atone end 20 and pulled away from the hip stem 2. As the sleeve 14 ispulled from between the mating tapers, it is able to stretch further togo over the articulating head 10. Alternatively the sleeve can be madeto break to allow it to be removed. The sleeve can also be removed bygripping it and pulling it sideways 24 away from the neck so that itbreaks along one side and wipes the tapers as it is pulled from betweenthem. The sleeve can be textured to facilitate the sleeve 14 wiping awaydebris. The sleeve can also be made of an absorbent material tofacilitate absorbing fluid from the mating taper surfaces. Where thesleeve is designed to break during removal, it can be made of anon-stretching material.

[0019] In another embodiment, the sleeve 14 is pulled from the male 12taper just as it is being inserted into the female taper 6 but withoutbeing pinched between the tapers. In this case the sleeve's 14 purposeis to protect the male taper 12 from contamination as it is insertedthrough the wound. Just prior to assembling the tapers, the sleeve 14 ispulled away to expose the clean male taper 12. The tapers are thenimpacted and locked together. To further protect the male taper 12 fromcontamination, the sleeve 14 can be made of a fluid impervious materialsuch as a polymer film.

[0020]FIGS. 3 and 4 show another illustrative embodiment of a sleeve 30for a head and neck 32 with a male taper 34. This sleeve 30 includes aportion 36 for covering the neck and a portion 38 for covering the head.A tab 40 extends from the sleeve 30 to facilitate its removal over 42the head. The tab 40 can be a continuation of the material of the sleeve30, or it can be a separate structure attached to the sleeve 30. Forexample, a knit sleeve could be made so that the knitting process iscontinued to form a knit extension from the sleeve. Alternatively, ayarn, bias tape or other material can be sewn or adhered to the sleeve.Similar tabs can be provided on sleeves made of non-woven or film-likematerials.

[0021]FIGS. 5 and 6 show another illustrative embodiment of a sleeve 41.This sleeve 41 is shown in conjunction with a stem 43 having a shaft 44for insertion into the intramedullary canal of a femur and a neck with amale taper 46 having an external taper engaging surface for engaging anarticulating head 48. The head includes a female taper 50 having aninternal taper engaging surface for receiving the male taper 46 of thestem 43. The male taper 46 is received by the female taper 50 with theirengaging surfaces in overlying engagement. The illustrative tapers 46,50 form a locking junction that can be locked by impacting themtogether. The sleeve 41 includes a sidewall 52 forming a hollow cylinderwith opposite open ends 54, 56. Tabs 58, 60 extend from one end 56 ofthe sleeve 41.

[0022] In use, the sleeve 41 functions similarly to the sleeve 14 ofFIGS. 1 and 2. The partially covered taper 46 is loosely inserted intothe female taper 50 with the sleeve 41 positioned between the overlyingtaper engaging surfaces. Prior to locking the tapers 46, 50 together,the sleeve is gripped by one end 56 and pulled from between the tapersto wipe the taper surfaces clean just before the tapers are lockedtogether. The sleeve 41 can be gripped with a pair of forceps at one end56. Alternatively, one or both of the tabs 58, 60 can be gripped andpulled to remove the sleeve. For a stretchable sleeve 41, it will turnwrong side out as it is pulled 61 from between the mating tapers andover the head 48. Alternatively the sleeve 41 can be made to break toallow it to be removed. The sleeve 41 can also be removed by gripping itand pulling it sideways 62 away from the neck so that it breaks alongone side and wipes the tapers as it is pulled from between them. Thevarious alternative materials applicable to the sleeve 14 of FIGS. 1 and2 also apply to this sleeve 41.

[0023]FIGS. 7 and 8 show another illustrative embodiment of a sleeve 63in use with a stem 64 having a female taper 65 with an internal taperengaging surface. This sleeve 63 comprises a body with opposite ends 66,67 and fits within the female taper 65 to cover at least a portion ofthe internal taper engaging surface. In this embodiment, the sleeve 63acts like a plug to protect the female taper 65. A tab 68 is attached tothe sleeve 63 to facilitate its removal.

[0024] In use, the sleeve 63 is inserted into the female taper 65. Thestem 64 is inserted through the wound into the femur. The sleeve is thengripped at one end 66 and removed 57 from the female taper 65 to exposeand/or clean the taper for receiving a mating component such as a headand neck with a male taper. Tab 68 extends from the female taper 65 andmay be gripped to facilitate removal of the sleeve 63.

[0025]FIG. 9 shows another illustrative embodiment of a sleeve 69 forcleaning an implant stem 70. The sleeve 69 includes a sidewall 71forming a hollow cylinder with opposite open ends 72, 73. The sleeve 69can be made from a variety of materials and can include a tab tofacilitate removal as described relative to the other embodiments. Inthe illustrative embodiment, it is shown as a woven or knit, absorbentfabric than can be fit over the stem 70 similar to a sock. The structureof the fabric allows it to stretch to fit over the stem in close-fittingrelationship.

[0026] In use, the sleeve 69 is slipped onto the stem 70. The stem 70 isinserted through the wound and then the sleeve 69 is slid along 74 thestem 70 to clean the stem. One particular use for the sleeve 69 is towipe the stem 70 as it is being inserted into a mass of cement placed ina bone to fix the stem 70 in place. In this case the sleeve 69 is placedon the stem, the stem inserted through the wound toward the cement, andas the stem enters the cement, the sleeve is slid along the stem toclean it just forward of the stem-cement interface.

[0027]FIGS. 10 and 11 show an embodiment of a sleeve 75 comprising aprotective film or bag 76. The sleeve 75 has ends 77, 78 that can beopened or closed. In the case where the ends are closed, they are madeso that the sleeve 75 can be torn, or the implant pushed through thesleeve 75, to facilitate removal of the sleeve 75 from the implant. Thesleeve 75 in FIG. 10 is shown with a hip stem 79. In use, the sleeve 75is positioned around the stem to protect it from contamination duringinsertion through the wound toward a femur 80 containing a mass ofcement for receiving the stem 79. The stem is inserted through the wounduntil it is adjacent the cement. As the stem 75 is inserted into thecement, the sleeve 75 is withdrawn 82 to progressively expose the cleanstem 79.

[0028] The sleeve 75 in FIG. 11 is shown with a femoral knee jointcomponent 90. In this case, the sleeve 75 can be used to protect cementthat has been pre-applied to the component 90. In use, cement is appliedto the component 90. The sleeve 75 is then positioned around thecomponent to protect it from contamination during insertion through thewound toward a prepared distal end of a femur. The component is insertedthrough the wound until it is adjacent the receiving bone surface. Asthe component 90 is inserted into engagement with the bone, the sleeve75 is withdrawn to expose the uncontaminated stem and pre-appliedcement.

[0029] Another illustrative application of a sleeve 75 of this type isfor use with an implant having a bone growth surface; e.g. fiber metal,trabecular metal, sintered beads, ceramics, plasma sprayed surfaces,grit blasted surfaces, and/or bone growth proteins applied to thesurface, and the like. In this case, the sleeve would protect thesurface from contamination from wound debris and fluids that mightinterfere with bone growth at the surface. Where materials such as bonegrowth proteins are applied to the surface, the sleeve would prevent thematerials from being inadvertently removed as the surface passes throughthe wound. Some of the bone growth materials mentioned can be very roughand might tend to abrade and trap contaminates from the wound on theirpassing. Therefore, the sleeve 75 can be used to protect the wound fromabrasion by such a rough implant surface. A sleeve for this purpose cantake any of the forms previously described. A sleeve having a smoothand/or slippery surface can be used to ease the passage of the implant.A metal foil or a foil/polymer laminate can also be used and is toughand resistant to abrasion. A foil made of a biocompatible material suchas titanium or stainless steel may be advantageously used.

[0030] The invention has been described in the context of a number ofembodiments. These embodiments have been for illustration only and it isto be understood that the illustrated aspects of the invention areapplicable to a variety of implants and not just those shown. The sleevecan be pre-applied and packaged with the implant or it can be applied atthe time of surgery. Various other modifications may be made to theseembodiments without departing from the spirit and scope of the inventiondefined by the appended claims.

What is claimed is:
 1. A sleeve and implant combination comprising: afirst implant component having a first engaging portion; a sleevemounted on the first component and surrounding at least a portion ofsaid first engaging portion; a second implant component having a secondengaging portion engaging the first engaging portion with the sleevepositioned between the first and second engaging portions, the sleevebeing removable from the first engaging portion while the components areso engaged so that the sleeve wipes the engaging portions as it isremoved.
 2. The sleeve and implant combination of claim 1 wherein thesleeve comprises a material selected from the group consisting of aknitted material, a woven material, a non-woven fibrous material, afilm, a foil, and a laminate of a foil and a polymer.
 3. The sleeve andimplant combination of claim 1 wherein the sleeve is made of astretchable material so that it can be stretched to remove it from thefirst component.
 4. The sleeve and implant combination of claim 3wherein the sleeve is made of a knitted material.
 5. The sleeve andimplant combination of claim 1 wherein the sleeve has a texturedsurface.
 6. The sleeve and implant combination of claim 1 wherein thesleeve is made of an absorbent material.
 7. The sleeve and implantcombination of claim 1 wherein the sleeve is made of a polymer film. 8.The sleeve and implant combination of claim 1 wherein the sleeve isfrangible so that it can be removed from the first component.
 9. Thesleeve and implant combination of claim 8 wherein the sleeve isfrangible along a predetermined portion.
 10. The sleeve and implantcombination of claim 1 wherein the sleeve further comprises a tabextending from the sleeve to facilitate gripping the sleeve.
 11. Animplant and sleeve combination for insertion into a patient's bodythrough a wound, the combination comprising: an implant; a sleevecovering a portion of the implant, the sleeve being slidable along theimplant to wipe the implant to clean the implant after it passes throughsaid wound.
 12. The sleeve and implant combination of claim 11 whereinthe sleeve includes a ring of material closely encircling a portion ofthe implant.
 13. The sleeve and implant combination of claim 11 whereinthe sleeve includes a bag-like covering portion.
 14. The sleeve andimplant combination of claim 13 wherein the sleeve is made of a polymerfilm.
 15. The sleeve and implant combination of claim 11 wherein thesleeve includes a plug of material fitting within a female portion ofthe implant.
 16. An implant and cover combination for insertion into apatient's body through a wound, the combination comprising: an implantincluding a female engaging feature having an internal mating surface;and a cover covering at least a portion of the internal mating surfaceto prevent contamination of the internal mating surface as the implantis inserted through said wound, the cover being removable after theimplant is inserted through said wound.
 17. The implant and covercombination of claim 15 wherein the cover further comprises a tabextending from the cover to facilitate gripping the cover.
 18. Animplant for anchoring in a surgical site accessed through a wound, theimplant comprising: a body having an anchoring portion; and a sleevesurrounding at least a portion of the anchoring portion, the sleevebeing removable from the anchoring portion after the body passes throughthe wound and as it is being anchored.
 19. The sleeve and implantcombination of claim 18 wherein the sleeve is made of a stretchablematerial so that it can be stretched to remove it from the firstcomponent.
 20. The sleeve and implant combination of claim 19 whereinthe sleeve is made of a knitted material.
 21. The sleeve and implantcombination of claim 18 wherein the sleeve has a textured surface. 22.The sleeve and implant combination of claim 18 wherein the sleeve ismade of an absorbent material.
 23. The sleeve and implant combination ofclaim 18 wherein the sleeve is made of a polymer film.
 24. The sleeveand implant combination of claim 18 wherein the sleeve is frangible sothat it can be removed from the first component.
 25. The sleeve andimplant combination of claim 24 wherein the sleeve is frangible along apredetermined portion.
 26. The sleeve and implant combination of claim18 wherein the sleeve further comprises a tab extending from the sleeveto facilitate gripping the sleeve.
 27. The sleeve and implantcombination of claim 18 wherein the sleeve includes a ring of materialclosely encircling a portion of the implant.
 28. The sleeve and implantcombination of claim 18 wherein the anchoring portion includes a bonegrowth surface.
 29. The sleeve and implant combination of claim 28wherein the bone growth surface comprises a material selected from thegroup consisting of fiber metal, trabecular metal, sintered beads,ceramics, plasma sprayed surfaces, grit blasted surfaces, and bonegrowth proteins.
 30. The sleeve and implant combination of claim 29wherein the sleeve comprises a material selected from the groupconsisting of a film, a foil, and a laminate of a foil and a polymer.31. The sleeve and implant combination of claim 18 wherein the sleevecomprises a material selected from the group consisting of a knittedmaterial, a woven material, a non-woven fibrous material, a film, afoil, and a laminate of a foil and a polymer.
 32. The sleeve and implantcombination of claim 18 wherein the anchoring portion is a cementingportion.
 33. The sleeve and implant combination of claim 32 wherein thering of material is slidable along the cementing portion to wipe thecementing portion clean as it is being cemented.
 34. The sleeve andimplant combination of claim 32 wherein the sleeve includes a bag. 35.The sleeve and implant combination of claim 34 wherein the sleeve ismade of a polymer film.
 36. The sleeve and implant combination of claim32 wherein the sleeve is retractable to expose the cementing portion asit is being cemented.
 37. The sleeve and implant combination of claim 36wherein the sleeve has a closed end that is breakable so that thecementing portion can be pushed through the closed end to expose thecementing portion as it is being cemented.
 38. The sleeve and implantcombination of claim 32 further comprising cement applied to at least aportion of the cementing portion, the sleeve surrounding at least aportion of the cement and cementing portion.
 39. The sleeve and implantcombination of claim 38 wherein the sleeve includes a bag.
 40. Thesleeve and implant combination of claim 39 wherein the sleeve is made ofa polymer film.
 41. The sleeve and implant combination of claim 38wherein the sleeve is retractable to expose the cementing portion as itis being cemented.
 42. The sleeve and implant combination of claim 41wherein the sleeve has a closed end that is breakable so that thecementing portion can be pushed through the closed end to expose thecementing portion as it is being cemented.
 43. A sleeve for a femoralhip implant for insertion through a surgical wound and into a femur; theimplant including a stem having a first end for insertion into theintramedullary canal of the femur, a second end with a taper junction,and a modular head member with a complimentary taper junction forengaging the stem taper junction; the sleeve comprising: a sleeve bodyfor covering at least a portion of the implant as the implant isinserted through the surgical wound.
 44. The sleeve of claim 43 whereinthe sleeve covers a portion of one of the head and stem complementarytaper junctions.
 45. The sleeve of claim 44 wherein the sleeve ispositioned between the complementary taper junctions as they are engagedso that as the sleeve is removed it wipes the complementary taperjunctions.
 46. The sleeve of claim 44 wherein the sleeve is fluidimpervious to prevent contaminants from reaching the portion of thetaper junction as the stem is inserted through the wound.
 47. The sleeveof claim 43 wherein the sleeve includes a ring of material closelyencircling a portion of the implant and being slidable along the implantto wipe the implant to clean the implant after it passes through saidwound.
 48. The sleeve of claim 47 wherein the ring of material encirclesthe first end of the stem.
 49. The sleeve of claim 43 wherein the sleeveincludes a bag.
 50. The sleeve of claim 49 wherein the sleeve is made ofa polymer film.
 51. The sleeve of claim 50 wherein the sleeve isretractable to expose the first end of the stem as it is inserted intothe intramedullary canal.
 52. The sleeve of claim 51 wherein the sleevehas a closed end that is breakable so that the first end of the stem canbe pushed through the closed end to expose the first end of the stem asit is inserted into the intramedullary canal.
 53. A method of insertingan implant through a wound and into a surgical site, the methodcomprising the steps of: covering a portion of the implant with asleeve; inserting the covered portion through the wound; removing thesleeve; and seating the implant.
 54. The method of claim 53 furthercomprising the steps of: placing cement at the surgical site; insertingthe covered portion adjacent the cement; and removing the sleeve as theportion is further inserted into the cement.
 55. The method of claim 53further comprising the steps of: assembling the covered portion with acomplementary mating implant component with the sleeve between the twomating components; and wiping the mating components clean by pulling thesleeve from between them.
 56. The method of claim 53 further comprisingthe steps of: inserting the covered portion adjacent a bone; andremoving the sleeve as the portion is further inserted into the bone.57. The method of claim 53 wherein covering a portion of the implantwith a sleeve includes covering a male mating portion of an implant witha sleeve.
 58. The method of claim 53 wherein covering a portion of theimplant with a sleeve includes covering a female mating portion of animplant with a sleeve.